Commit Graph

3872 Commits

Author SHA1 Message Date
Graham Hunter b302561b76 [SVE][IR] Scalable Vector size queries and IR instruction support
* Adds a TypeSize struct to represent the known minimum size of a type
  along with a flag to indicate that the runtime size is a integer multiple
  of that size
* Converts existing size query functions from Type.h and DataLayout.h to
  return a TypeSize result
* Adds convenience methods (including a transparent conversion operator
  to uint64_t) so that most existing code 'just works' as if the return
  values were still scalars.
* Uses the new size queries along with ElementCount to ensure that all
  supported instructions used with scalable vectors can be constructed
  in IR.

Reviewers: hfinkel, lattner, rkruppe, greened, rovka, rengolin, sdesmalen

Reviewed By: rovka, sdesmalen

Differential Revision: https://reviews.llvm.org/D53137

llvm-svn: 374042
2019-10-08 12:53:54 +00:00
Kai Nacke c9ddda8405 [Tools] Mark output of tools as text if it is text
Several LLVM tools write text files/streams without using OF_Text.
This can cause problems on platforms which distinguish between
text and binary output. This PR adds the OF_Text flag for the
following tools:

- llvm-dis
- llvm-dwarfdump
- llvm-mca
- llvm-mc (assembler files only)
- opt (assembler files only)
- RemarkStreamer (used e.g. by opt)

Reviewers: rnk, vivekvpandya, Bigcheese, andreadb

Differential Revision: https://reviews.llvm.org/D67696

llvm-svn: 374024
2019-10-08 08:21:20 +00:00
Chen Zheng 9806a1d5f9 [ConstantRange] [NFC] replace addWithNoSignedWrap with addWithNoWrap.
llvm-svn: 374016
2019-10-08 03:00:31 +00:00
Reid Kleckner f9b67b810e [X86] Add new calling convention that guarantees tail call optimization
When the target option GuaranteedTailCallOpt is specified, calls with
the fastcc calling convention will be transformed into tail calls if
they are in tail position. This diff adds a new calling convention,
tailcc, currently supported only on X86, which behaves the same way as
fastcc, except that the GuaranteedTailCallOpt flag does not need to
enabled in order to enable tail call optimization.

Patch by Dwight Guth <dwight.guth@runtimeverification.com>!

Reviewed By: lebedev.ri, paquette, rnk

Differential Revision: https://reviews.llvm.org/D67855

llvm-svn: 373976
2019-10-07 22:28:58 +00:00
Jordan Rose fdaa742174 Second attempt to add iterator_range::empty()
Doing this makes MSVC complain that `empty(someRange)` could refer to
either C++17's std::empty or LLVM's llvm::empty, which previously we
avoided via SFINAE because std::empty is defined in terms of an empty
member rather than begin and end. So, switch callers over to the new
method as it is added.

https://reviews.llvm.org/D68439

llvm-svn: 373935
2019-10-07 18:14:24 +00:00
Erich Keane 8a410bcef0 Fix Calling Convention through aliases
r369697 changed the behavior of stripPointerCasts to no longer include
aliases.  However, the code in CGDeclCXX.cpp's createAtExitStub counted
on the looking through aliases to properly set the calling convention of
a call.

The result of the change was that the calling convention mismatch of the
call would be replaced with a llvm.trap, causing a runtime crash.

Differential Revision: https://reviews.llvm.org/D68584

llvm-svn: 373929
2019-10-07 17:28:03 +00:00
whitequark b63db94fa5 [LLVM-C] Add bindings to create macro debug info
Summary: The C API doesn't have the bindings to create macro debug information.

Reviewers: whitequark, CodaFi, deadalnix

Reviewed By: whitequark

Subscribers: aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58334

llvm-svn: 373903
2019-10-07 13:57:13 +00:00
Kevin P. Neal 1c3d19c82d [FPEnv] Add constrained intrinsics for lrint and lround
Earlier in the year intrinsics for lrint, llrint, lround and llround were
added to llvm. The constrained versions are now implemented here.

Reviewed by:	andrew.w.kaylor, craig.topper, cameron.mcinally
Approved by:	craig.topper
Differential Revision:	https://reviews.llvm.org/D64746

llvm-svn: 373900
2019-10-07 13:20:00 +00:00
Guillaume Chatelet d400d45150 [Alignment][NFC] Remove StoreInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, bollu, jdoerfert

Subscribers: hiraditya, asbirlea, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68268

llvm-svn: 373595
2019-10-03 13:17:21 +00:00
Kerry McLaughlin 76365b3b24 [IntrinsicEmitter] Add overloaded type VecOfBitcastsToInt for SVE intrinsics
Summary:
This allows intrinsics such as the following to be defined:
 - declare <n x 4 x i32> @llvm.something.nxv4f32(<n x 4 x i32>, <n x 4 x i1>, <n x 4 x float>)

...where <n x 4 x i32> is derived from <n x 4 x float>, but
the element needs bitcasting to int.

Reviewers: c-rhodes, sdesmalen, rovka

Reviewed By: c-rhodes

Subscribers: tschuett, hiraditya, jdoerfert, llvm-commits, cfe-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D68021

llvm-svn: 373437
2019-10-02 09:25:02 +00:00
Simon Pilgrim 30f76caa46 DIExpression::createFragmentExpression - silence static analyzer DIExpression* null dereference warning with an assertion. NFCI.
llvm-svn: 373326
2019-10-01 11:25:38 +00:00
Simon Pilgrim d71315f2ae ConstantFold - ConstantFoldSelectInstruction - assume constant vector elements are constant. NFCI.
Goes a bit further than rL372743 which added the early out - elements should be Constant so use cast<Constant> instead (and rely on the assert if anything fails).

llvm-svn: 373321
2019-10-01 10:22:01 +00:00
Alina Sbirlea ad88884658 [LegacyPassManager] Attempt to fix BasicBlockManager
Temporarily fix BaiscBlockManager based on the code in the other
managers.
Replacement of all uses of the BasicBlockPass to follow.

Resolves PR42264.

llvm-svn: 373235
2019-09-30 17:23:49 +00:00
Kerry McLaughlin 01b84e175c [AArch64][SVE] Implement punpk[hi|lo] intrinsics
Summary:
Adds the following two intrinsics:
  - int_aarch64_sve_punpkhi
  - int_aarch64_sve_punpklo

This patch also contains a fix which allows LLVMHalfElementsVectorType
to forward reference overloadable arguments.

Reviewers: sdesmalen, rovka, rengolin

Reviewed By: sdesmalen

Subscribers: tschuett, kristof.beyls, hiraditya, rkruppe, psnobl, greened, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67830

llvm-svn: 373232
2019-09-30 17:10:21 +00:00
Guillaume Chatelet ab11b9188d [Alignment][NFC] Remove AllocaInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, arsenm, jvesely, nhaehnle, eraman, hiraditya, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68141

llvm-svn: 373207
2019-09-30 13:34:44 +00:00
Chen Zheng bfec045626 [ConstantRange] add helper function addWithNoWrap().
Differential Revision: https://reviews.llvm.org/D67339

llvm-svn: 373205
2019-09-30 12:57:53 +00:00
Guillaume Chatelet 17380227e8 [Alignment][NFC] Remove LoadInst::setAlignment(unsigned)
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet, jdoerfert

Subscribers: hiraditya, asbirlea, cfe-commits, llvm-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D68142

llvm-svn: 373195
2019-09-30 09:37:05 +00:00
Anton Afanasyev f7a428ecaa [TimeProfiler] Fix "OptModule" section and add new "Backend" sections
Remove unnecessary "OptModule" section. Add "PerFunctionPasses",
"PerModulePasses" and "CodeGenPasses" sections under "Backend" section.

llvm-svn: 373142
2019-09-28 07:14:12 +00:00
Guillaume Chatelet 18f805a7ea [Alignment][NFC] Remove unneeded llvm:: scoping on Align types
llvm-svn: 373081
2019-09-27 12:54:21 +00:00
Guillaume Chatelet 6200a5689a [NFC] Rearrange Value::getPointerAlignment
Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67918

llvm-svn: 372987
2019-09-26 15:13:05 +00:00
Nick Lewycky f57e968dd0 Improve C API support for atomicrmw and cmpxchg.
atomicrmw and cmpxchg have a volatile flag, so allow them to be get and set with LLVM{Get,Set}Volatile. atomicrmw and fence have orderings, so allow them to be get and set with LLVM{Get,Set}Ordering. Add missing LLVMAtomicRMWBinOpFAdd and LLVMAtomicRMWBinOpFSub enum constants. AtomicCmpXchg also has a weak flag, add a getter/setter for that too. Add a getter/setter for the binary-op of an atomicrmw.

atomicrmw and cmpxchg have a volatile flag, so allow it to be set/get with LLVMGetVolatile and LLVMSetVolatile. Add missing LLVMAtomicRMWBinOpFAdd and LLVMAtomicRMWBinOpFSub enum constants. AtomicCmpXchg also has a weak flag, add a getter/setter for that too. Add a getter/setter for the binary-op of an atomicrmw.

Add LLVMIsA## for CatchSwitchInst, CallBrInst and FenceInst, as well as AtomicCmpXchgInst and AtomicRMWInst.

Update llvm-c-test to include atomicrmw and fence, and to copy volatile for the four applicable instructions.

Differential Revision: https://reviews.llvm.org/D67132

llvm-svn: 372938
2019-09-26 00:58:55 +00:00
Nick Desaulniers 93d87260f1 [Verifier] add invariant check for callbr
Summary:
The list of indirect labels should ALWAYS have their blockaddresses as
argument operands to the callbr (but not necessarily the other way
around).  Add an invariant that checks this.

The verifier catches a bad test case that was added recently in r368478.
I think that was a simple mistake, and the test was made less strict in
regards to the precise addresses (as those weren't specifically the
point of the test).

This invariant will be used to find a reported bug.

Link: https://www.spinics.net/lists/arm-kernel/msg753473.html
Link: https://github.com/ClangBuiltLinux/linux/issues/649

Reviewers: craig.topper, void, chandlerc

Reviewed By: void

Subscribers: ychen, lebedev.ri, javed.absar, kristof.beyls, hiraditya, llvm-commits, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67196

llvm-svn: 372923
2019-09-25 22:28:27 +00:00
Simon Pilgrim b2befe47dc Fix analyzer TypeAttributeImpl::anchor() override.
TypeAttributeImpl inherits from EnumAttributeImpl which already defines anchor() as a virtual, so we should override this instead of redeclaring it.

llvm-svn: 372877
2019-09-25 14:23:25 +00:00
Simon Pilgrim 806bfa2636 Fix cppcheck variable shadow warning. NFCI.
llvm-svn: 372872
2019-09-25 13:45:36 +00:00
Simon Pilgrim 367df1ebbc Add missing ExplicitTy default initialization to ConstantExprKeyType constructors.
Fixes cppcheck uninitialized variable warnings

llvm-svn: 372871
2019-09-25 13:38:54 +00:00
Thomas Preud'homme 5f738940b5 Regex: Make "match" and "sub" const member functions
Summary:
The Regex "match" and "sub" member functions were previously not "const"
because they wrote to the "error" member variable. This commit removes
those assignments, and instead assumes that the validity of the regex
is already known after the initial compilation of the regular
expression. As a result, these member functions were possible to make
"const". This makes it easier to do things like pre-compile Regexes
up-front, and makes "match" and "sub" thread-safe. The error status is
now returned as an optional output, which also makes the API of "match"
and "sub" more consistent with each other.

Also, some uses of Regex that could be refactored to be const were made const.

Patch by Nicolas Guillemot

Reviewers: jankratochvil, thopre

Subscribers: llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67241

llvm-svn: 372764
2019-09-24 14:42:36 +00:00
Simon Pilgrim 734d3f49ad SafepointIRVerifier - silence static analyzer dyn_cast<Instruction> null dereference warnings. NFCI.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<Instruction> directly and if not assert will fire for us.

llvm-svn: 372758
2019-09-24 13:57:44 +00:00
Simon Pilgrim 182d4874fd ConstantFold - silence static analyzer dyn_cast<> null dereference warning. NFCI.
Early out if the vector element is not Constant.

llvm-svn: 372743
2019-09-24 12:30:13 +00:00
Simon Pilgrim cc972981d4 Fix cppcheck "reduce variable scope" warning. NFCI.
llvm-svn: 372742
2019-09-24 12:30:07 +00:00
Simon Pilgrim 06cdcb5f68 [IR] IntrinsicInst - silence static analyzer dyn_cast<> null dereference warnings. NFCI.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<> directly and if not assert will fire for us.

llvm-svn: 372733
2019-09-24 11:40:45 +00:00
Guillaume Chatelet a06c13b1f9 [Alignment][NFC] Migrate Instructions to Align
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67917

llvm-svn: 372613
2019-09-23 14:23:37 +00:00
Simon Pilgrim 0860934291 Function::BuildLazyArguments() - fix "variable used but never read" analyzer warning. NFCI.
Simplify the code by separating the masking of the SDC variable from using it.

llvm-svn: 372598
2019-09-23 12:49:39 +00:00
Guillaume Chatelet 1ae7905fc8 [Alignment][NFC] DataLayout migration to llvm::Align
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: jholewinski, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67914

llvm-svn: 372596
2019-09-23 12:41:36 +00:00
Guillaume Chatelet 046a16b8fb [Alignment][NFC] Switch DataLayout private members to llvm::Align
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67836

llvm-svn: 372558
2019-09-23 08:38:36 +00:00
Simon Pilgrim 638933acab Verifier - silence static analyzer dyn_cast<VectorType> null dereference warnings. NFCI.
The static analyzer is warning about potential null dereferences, but we should be able to use cast<VectorType> directly and if not assert will fire for us.

llvm-svn: 372529
2019-09-22 21:01:23 +00:00
Guillaume Chatelet 6c127cdb99 [Alignment][NFC] migrate DataLayout internal struct to llvm::Align
Summary:
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

With this patch the PointerAlignElem struct goes from 20B to 16B.

Reviewers: courbet

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67400

llvm-svn: 372390
2019-09-20 13:40:31 +00:00
David Tellenbach 2a47c77e72 [FastISel] Fix insertion of unconditional branches during FastISel
The insertion of an unconditional branch during FastISel can differ depending on
building with or without debug information. This happens because FastISel::fastEmitBranch
emits an unconditional branch depending on the size of the current basic block
without distinguishing between debug and non-debug instructions.

This patch fixes this issue by ignoring debug instructions when getting the size
of the basic block.

Reviewers: aprantl

Reviewed By: aprantl

Subscribers: ormris, aprantl, hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67703

llvm-svn: 372389
2019-09-20 13:22:59 +00:00
Kerry McLaughlin 22a8f35ce0 [IntrinsicEmitter] Add overloaded types for SVE intrinsics (Subdivide2 & Subdivide4)
Summary:
Both match the type of another intrinsic parameter of a vector type, but where each element is subdivided to form a vector with more elements of a smaller type.

Subdivide2Argument allows intrinsics such as the following to be defined:
 - declare <vscale x 4 x i32> @llvm.something.nxv4i32(<vscale x 8 x i16>)

Subdivide4Argument allows intrinsics such as:
 - declare <vscale x 4 x i32> @llvm.something.nxv4i32(<vscale x 16 x i8>)

Tests are included in follow up patches which add intrinsics using these types.

Reviewers: sdesmalen, SjoerdMeijer, greened, rovka

Reviewed By: sdesmalen

Subscribers: rovka, tschuett, jdoerfert, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67549

llvm-svn: 372380
2019-09-20 09:48:21 +00:00
Adrian Prantl 0779dffbd4 Remove the obsolete BlockByRefStruct flag from LLVM IR
DIFlagBlockByRefStruct is an unused DIFlag that originally was used by
clang to express (Objective-)C block captures in debug info. For the
last year Clang has been emitting complex DIExpressions to describe
block captures instead, which makes all the code supporting this flag
redundant.

This patch removes the flag and all supporting "dead" code, so we can
reuse the bit for something else in the future.

Since this only affects debug info generated by Clang with the block
extension this mostly affects Apple platforms and I don't have any
bitcode compatibility concerns for removing this. The Verifier will
reject debug info that uses the bit and thus degrade gracefully when
LTO'ing older bitcode with a newer compiler.

rdar://problem/44304813

Differential Revision: https://reviews.llvm.org/D67453

llvm-svn: 372272
2019-09-18 22:38:56 +00:00
Amy Huang 68eae49859 Add AutoUpgrade function to add new address space datalayout string to existing datalayouts.
Summary:
Add function to AutoUpgrade to change the datalayout of old X86 datalayout strings.
This adds "-p270:32:32-p271:32:32-p272:64:64" to X86 datalayouts that are otherwise valid
and don't already contain it.

This also removes the compatibility changes in https://reviews.llvm.org/D66843.
Datalayout change in https://reviews.llvm.org/D64931.

Reviewers: rnk, echristo

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67631

llvm-svn: 372267
2019-09-18 22:15:58 +00:00
Francis Visoiu Mistrih ba2e752c52 [Remarks] Allow the RemarkStreamer to be used directly with a stream
The filename in the RemarkStreamer should be optional to allow clients
to stream remarks to memory or to existing streams.

This introduces a new overload of `setupOptimizationRemarks`, and avoids
enforcing the presence of a filename at different places.

llvm-svn: 372195
2019-09-18 01:04:45 +00:00
Kerry McLaughlin e55b3bf40e [SVE][Inline-Asm] Add constraints for SVE predicate registers
Summary:
Adds the following inline asm constraints for SVE:
  - Upl: One of the low eight SVE predicate registers, P0 to P7 inclusive
  - Upa: SVE predicate register with full range, P0 to P15

Reviewers: t.p.northover, sdesmalen, rovka, momchil.velikov, cameron.mcinally, greened, rengolin

Reviewed By: rovka

Subscribers: javed.absar, tschuett, rkruppe, psnobl, cfe-commits, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D66524

llvm-svn: 371967
2019-09-16 09:45:27 +00:00
Yevgeny Rouban bdfe84ad11 Make SwitchInstProfUpdateWrapper strict permanently
We have been using -switch-inst-prof-update-wrapper-strict
set to true by default for some time. It is time to remove
the safety stuff and make SwitchInstProfUpdateWrapper
intolerant to inconsistencies in !prof branch_weights
metadata of SwitchInst.

This patch gets rid of the Invalid state of
SwitchInstProfUpdateWrapper and the option
-switch-inst-prof-update-wrapper-strict. So there is only
two states: changed and unchanged.

Reviewers: davidx, nikic, eraman, reames, chandlerc
Reviewed By: davidx
Differential Revision: https://reviews.llvm.org/D67435

llvm-svn: 371707
2019-09-12 03:41:34 +00:00
Petr Hosek 7bdad08429 Reland "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371635
2019-09-11 16:19:50 +00:00
Dmitri Gribenko 57256af307 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This reverts commit r371584. It introduced a dependency from compiler-rt
to llvm/include/ADT, which is problematic for multiple reasons.

One is that it is a novel dependency edge, which needs cross-compliation
machinery for llvm/include/ADT (yes, it is true that right now
compiler-rt included only header-only libraries, however, if we allow
compiler-rt to depend on anything from ADT, other libraries will
eventually get used).

Secondly, depending on ADT from compiler-rt exposes ADT symbols from
compiler-rt, which would cause ODR violations when Clang is built with
the profile library.

llvm-svn: 371598
2019-09-11 09:16:17 +00:00
Petr Hosek 394a8ed8f1 clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371584
2019-09-11 01:09:16 +00:00
Petr Hosek 7d1757aba8 Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"
This reverts commit r371484: this broke sanitizer-x86_64-linux-fast bot.

llvm-svn: 371488
2019-09-10 06:25:13 +00:00
Petr Hosek a10802fd73 clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM
This patch contains the basic functionality for reporting potentially
incorrect usage of __builtin_expect() by comparing the developer's
annotation against a collected PGO profile. A more detailed proposal and
discussion appears on the CFE-dev mailing list
(http://lists.llvm.org/pipermail/cfe-dev/2019-July/062971.html) and a
prototype of the initial frontend changes appear here in D65300

We revised the work in D65300 by moving the misexpect check into the
LLVM backend, and adding support for IR and sampling based profiles, in
addition to frontend instrumentation.

We add new misexpect metadata tags to those instructions directly
influenced by the llvm.expect intrinsic (branch, switch, and select)
when lowering the intrinsics. The misexpect metadata contains
information about the expected target of the intrinsic so that we can
check against the correct PGO counter when emitting diagnostics, and the
compiler's values for the LikelyBranchWeight and UnlikelyBranchWeight.
We use these branch weight values to determine when to emit the
diagnostic to the user.

A future patch should address the comment at the top of
LowerExpectIntrisic.cpp to hoist the LikelyBranchWeight and
UnlikelyBranchWeight values into a shared space that can be accessed
outside of the LowerExpectIntrinsic pass. Once that is done, the
misexpect metadata can be updated to be smaller.

In the long term, it is possible to reconstruct portions of the
misexpect metadata from the existing profile data. However, we have
avoided this to keep the code simple, and because some kind of metadata
tag will be required to identify which branch/switch/select instructions
are influenced by the use of llvm.expect

Patch By: paulkirth
Differential Revision: https://reviews.llvm.org/D66324

llvm-svn: 371484
2019-09-10 03:11:39 +00:00
Bjorn Pettersson 5e331e4ce8 [Intrinsic] Add the llvm.umul.fix.sat intrinsic
Summary:
Add an intrinsic that takes 2 unsigned integers with
the scale of them provided as the third argument and
performs fixed point multiplication on them. The
result is saturated and clamped between the largest and
smallest representable values of the first 2 operands.

This is a part of implementing fixed point arithmetic
in clang where some of the more complex operations
will be implemented as intrinsics.

Patch by: leonardchan, bjope

Reviewers: RKSimon, craig.topper, bevinh, leonardchan, lebedev.ri, spatel

Reviewed By: leonardchan

Subscribers: ychen, wuzish, nemanjai, MaskRay, jsji, jdoerfert, Ka-Ka, hiraditya, rjmccall, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D57836

llvm-svn: 371308
2019-09-07 12:16:14 +00:00
Nick Desaulniers 7a7bba2895 [IR] CallBrInst: scan+update arg list when indirect dest list changes
Summary:
There's an unspoken invariant of callbr that the list of BlockAddress
Constants in the "function args" list match the BasicBlocks in the
"other labels" list. (This invariant is being added to the LangRef in
https://reviews.llvm.org/D67196).

When modifying the any of the indirect destinations of a callbr
instruction (possible jump targets), we need to update the function
arguments if the argument is a BlockAddress whose BasicBlock refers to
the indirect destination BasicBlock being replaced.  Otherwise, many
transforms that modify successors will end up violating that invariant.
A recent change to the arm64 Linux kernel exposed this bug, which
prevents the kernel from booting.

I considered maintaining a mapping from indirect destination BasicBlock
to argument operand BlockAddress, but this ends up being a one to
potentially many (though usually one) mapping.  Also, the list of
arguments to a function (or more typically inline assembly) ends up
being less than 10.  The implementation is significantly simpler to just
rescan the full list of arguments. Because of the one to potentially
many relationship, the full arg list must be scanned (we can't stop at
the first instance).

Thanks to the following folks that reported the issue and helped debug
it:
* Nathan Chancellor
* Will Deacon
* Andrew Murray
* Craig Topper

Link: https://bugs.llvm.org/show_bug.cgi?id=43222
Link: https://github.com/ClangBuiltLinux/linux/issues/649
Link: https://lists.infradead.org/pipermail/linux-arm-kernel/2019-September/678330.html

Reviewers: craig.topper, chandlerc

Reviewed By: craig.topper

Subscribers: void, javed.absar, kristof.beyls, hiraditya, llvm-commits, nathanchance, srhines

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67252

llvm-svn: 371262
2019-09-06 21:50:11 +00:00